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00 buckshot works equally as well and can be placed in the tank from 75 yards away!
Does octane matter that much?
- Thread starter Westwood
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Hard to get ammo around here. I want to save my shells for the next election!00 buckshot works equally as well and can be placed in the tank from 75 yards away!
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Take each 00 out of the shells you have- drill a hole though each, lace them together with piano wire and coil them back into the shell.
Will open any door for you at the polling booths.
Huskybill
Addicted to ArboristSite
I got ammo wish I build a underground bunker instead, next election me and the burros are going gold mining.
I have cases of 12 ga 00/ 400gr slugs when the squirrels and chipmunks start throwing nuts make kababs, vaporized ready to eat. lol
JayPopple
ArboristSite Lurker
That is a difficult thing to answer there are too many variables. My dealer always recommended using the highest octane fuel I could buy. One reason was the saws run so hot the fuel boils in the tank and evaporated the volatiles off. Fuel in storage also lose those gases but when mixed with oil that process is reduced.
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I need to see video footage of that- fuel boiling in a chainsaw gas tank would be fun to see- from a distance.
Ethanol fuel = Farm subsidy
Won't low grade gas paired with 2-cycle oil be prone to carbon build-up?
Won't carbon embers lend to pre-ignition and spark knock?
I don't believe this is a 1-tank problem or even 1-can problem but a progressive issue that manufacturers recommendations reduce.
Changing gas is more likely a carb and mix issue. 87 is most likely an ethanol blend with differant density, specific gravity(SG), and viscosity.
This has all got to have some subtle effect on carburation and performance changes when changing fuel type(ethanol/e-free) and octane levels.
Won't low grade gas paired with 2-cycle oil be prone to carbon build-up?
Won't carbon embers lend to pre-ignition and spark knock?
I don't believe this is a 1-tank problem or even 1-can problem but a progressive issue that manufacturers recommendations reduce.
Changing gas is more likely a carb and mix issue. 87 is most likely an ethanol blend with differant density, specific gravity(SG), and viscosity.
This has all got to have some subtle effect on carburation and performance changes when changing fuel type(ethanol/e-free) and octane levels.
Best guess is ethanol laden gasoline requires about 5% more fuel delivery capacity at the 10% blend ratio, E85 is about 35% more fuel required. I worry more about aluminum/magnesium/steel reacting to the ethanol and the water it can hold. Too many times I have seen carb bodies corroded, steel gas tanks rusting and even engine internals rusting stemming from fuel problems. The one thing never mentioned that is really expensive is aluminum gas tanks in larger boats that get riddled with pin holes from ethanol blended gas. I think it is greatly exacerbated by moisture where the water fully saturates the ethanol to the point it falls out of suspension with the gasoline leading to puddling of water/ethanol. The bottom corners of fuel tanks and float bowl bottoms where a lean or slight angle that gravity pools it consistently is typically what I find when caught early on but once allowed to fester a little spreads rapidly like a rash. My theory on moisture in carbs is air is rapidly drawn across the venturies causing a large temperature differential leading to condensation during engine operation. Chainsaw carbs (more modern) typically drain back into the fuel tank over time where as 4 stroke carbs hold fuel inside them unless a fuel supply shutoff is used. Carb setups deliver a set fuel amount making for a overly rich air/fuel ratio when the engine is cold but just right once warm where as a fuel injection system will dial back or add fuel according to temperature, elevation readings etc. If a carb setup is run short times consistently over and over you end up with excessive carbon buildup and crank case oil diluted with fuel. Fuel ratio is not only important for power output but also for proper cooling of the engine and also cleaning and in some situations lubricating its internal parts. People claim standard pump fuel is cheaper to run but in carbureted small engines its often more expensive once you figure in the damages it causes and the fact it has less total energy resulting in more consumption. If you must use 10% pump fuel I highly suggest testing moisture content at every purchase, too many times I have seen fuel strait from the pump so saturated with water that it puddles once the tank is allowed to settle in the shade for a hour or two. Just as the small fuel tank on your equipment condensates so does the huge underground/above ground storage tanks when they are not full.
Dennbb
ArboristSite Member
Octane just slows the burn down and makes gas less volatile to prevent detonation, or pre ignition in high compression engines. If anything low octane will fire better cold than high test.
To shoot yourself if your side loses?
Pump Premium and regular have the same burn rate. It's actually beneficial to combust your fuel air mixture as fast as possible to prevent detonation so it makes no sense premium would be blended to burn slower.
Volatility is controlled by RVP requirements for both fuels to the same number.
Dennbb
ArboristSite Member
Nope
It's absolutely true. FWIW I see the Reid Vapor Pressures and the distillation curves from the refinery I work at on a daily basis.
The high octane burning slower thing is a internet old wives tail. Anything one does to slow down combustion increases risk of detonation and conversely anything you do to speed up combustion decreases risk of detonation. Things like squish band design, transfer port pointing, etc are all designed to speed up combustion and lessen detonation risk.
Smitty Smithsonite
ArboristSite Operative
When I bought my first motorcycle at age 17, an '84 Kawasaki KZ700, the general consensus was to run nothing but premium. It pained me to pay $1.30 a gallon when I could buy regular at the time for .89 cents. So I figured I'd split the difference and run 89 octane at $1.09 a gallon, and save a few cents. I'll never forget coming home from Hampton Beach on 495 towards the 140 exit in Upton, rolling on the throttle without downshifting, and hearing that "rattle"! I knew exactly what it was being a motorhead all through my youth. Never ran anything but premium after that!
That was a 4-stroke, too. When that happens in a 2-stroke, things have the potential to get so hot as to hole a piston pretty quick. Best to play it safe and pay the .40 cents, or whatever it is a gallon extra.
That was a 4-stroke, too. When that happens in a 2-stroke, things have the potential to get so hot as to hole a piston pretty quick. Best to play it safe and pay the .40 cents, or whatever it is a gallon extra.
The compression ratio of a chainsaw is so low, even a modded saw, that detonation isn't usually an issue. If it is its game over pretty quick in an air cooled two stroke.
The picture you posted is of pre ignition, not detonation. A hole in the center of the piston is always from pre ignition. Detonation always occurs at the outer edges of the piston, typically on the exhaust side of a two stroke. It presents itself as a sand blasted appearance. Detonation is not caused by colliding flame fronts from alternate ignition sources. It's caused by a normal ignition sequence that starts as a normal smooth combustion event, but as it reaches the edges of the combustion chamber the mixture breaks down due to heat and pressure and expiereance something akin to an explosion rather than a smooth combustion event.
If you google detonation you rarely get a real representation of what it actually is.
Smitty Smithsonite
ArboristSite Operative
I've always used the 2-terms to mean the same thing over the years, but technically you're correct.
I've understood it as detonation to be spontaneous combustion, like with a diesel, at some point in the combustion chamber not caused by the spark plug, usually caused by too low an octane rating fuel for the engine. Pre-ignition is usually caused by hot carbon, or a head gasket that protrudes into the combustion chamber, which glows & ignites the mixture before the plug. The end result is usually the same. I grabbed that pic off the net and figured someone would correct it. That was a pic from a big automotive parts company, too.
I used to see holed pistons in dirt bikes quite often, back when people set points up wrong, and advanced the timing too far.
I've understood it as detonation to be spontaneous combustion, like with a diesel, at some point in the combustion chamber not caused by the spark plug, usually caused by too low an octane rating fuel for the engine. Pre-ignition is usually caused by hot carbon, or a head gasket that protrudes into the combustion chamber, which glows & ignites the mixture before the plug. The end result is usually the same. I grabbed that pic off the net and figured someone would correct it. That was a pic from a big automotive parts company, too.
I used to see holed pistons in dirt bikes quite often, back when people set points up wrong, and advanced the timing too far.
Your understanding of what pre ignition and detonation are is spot on. And they are two different things that people more often then not confuse into one.
"Pre-detonation."
(A joke, for the humor impaired.)
(A joke, for the humor impaired.)
If I had a nickle for every time someone uttered that I'd be rich. Never mind there is no such thing."Pre-detonation."
(A joke, for the humor impaired.)
